Sounds realistic and engaging. You bring up a good point about publishing to the world vs. just to you as the teacher. I think the idea of a group work project after learning a skill set is a great idea. The lesson incorporates many different kinds of pedagogy, and many skills sets for students.
With the amount of time that it takes to set up a wiki, I wonder how you have them reference this page again. Would this be something that year after year would get added onto? How would all students set up a wiki (if this is the main skill set) or is one person setting it up for the group?